Body Surface Area Calculator
Estimate body surface area (BSA) from height and weight using the Mosteller equation commonly used for general reference.
How to use this calculator
- Enter height in centimetres and weight in kilograms.
- Review the worked example for body surface area calculator and compare the inputs with your own units.
- Change one assumption at a time and recalculate if you need a second scenario.
Mosteller equation
BSA in m² = square root of [height in cm × weight in kg ÷ 3600].
- The equation produces a formula estimate from the two measurements and is not an individual clinical assessment.
- The result is calculated from the values entered; the page does not independently verify assumptions, data quality or real-world suitability.
Worked examples
170 cm and 65 kg
Substitute a height of 170 cm and a weight of 65 kg in the equation.
sqrt(170 × 65 ÷ 3600) ≈ 1.752 m².
Estimated body surface area is about 1.752 m².
Understanding the result
A stated formula makes the calculation reproducible from the same height and weight.
BSA formulas can vary and the result should not be used to choose or adjust a medication dose.
Important notes
For clinical decisions, follow the relevant professional protocol and qualified clinician.
Displayed figures are rounded for readability. Preserve more precision during intermediate calculations and verify the labels and units before using the estimate.
Frequently asked questions
What does the Body Surface Area Calculator show?
A stated formula makes the calculation reproducible from the same height and weight.
What assumptions should I check?
For clinical decisions, follow the relevant professional protocol and qualified clinician.
Does this replace expert or authoritative guidance?
BSA formulas can vary and the result should not be used to choose or adjust a medication dose.
Related calculators
- Ideal Weight Calculator — Find your ideal body weight based on height, gender, and frame size.
- Surface Area Calculator — Calculate surface area for a rectangular prism, cylinder, or sphere.
- Body Fat Calculator — Estimate your body fat percentage using the US Navy method.
- Area Calculator — Calculate the area of a rectangle, circle, or triangle.
- Annulus Area Calculator — Calculate the area between two concentric circles from the outer and inner radii.
- BMI Calculator — Calculate your Body Mass Index (BMI) and see which weight category you fall into.
Related explanations
Learn the method behind the number or compare the terminology before using the calculator.
- How to Calculate Salary from an Hourly Rate — Convert hourly pay into weekly, monthly, and annual estimates and understand the assumptions behind the result.
- How to Calculate a Z-Score — Learn how a z-score shows how far a value is from the mean in standard-deviation units.
- Area — Understand area as the amount of two-dimensional surface inside a shape and review common formulas.
This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.